Vram and high res gaming

dagodeirosJan 12, 2013, 12:54 AM

I am getting mixed reviews / advice on this subject so I came to the one place I trust..

I am currently in the market for a graphics card to support 5760x1080. The ones I have my eyes on are the Evga GTX 670 4gb or the Evga GTX 680 2gb. I have heard from many different sources that a 4gb card would be better suited for higher resolution, while at the same time from as many sources stating that the Vram wall is impossible to reach in any normal scenario (only possible with HD Graphic modifications)and that 2gb would perform just as well. I do plan on getting a second of whichever card for SLI in the near future (3-4 months). I would prefer the gtx 680 2gb because I can get it for minimal price difference and it is a much better card, whereas a 4gb 680 would cost over $100 more.

Definitely get the 4GB version if you're going to SLI and play at 5760x1080. And no, 680 is not a much better card, it's just much more expensive. If you overclock both to same frequency, the difference in FPS is within margin of error.http://www.anandtech.com/bench/Product/598?vs=555

I think that redeemer's point is that the GTX 670 and 680 may have memory bandwidth performance problems before they run out of memory capacity on the 2GB models. To an extent, it is true, but there are a few situations where the 4GB models have an advantage. Only a few. Overall, they're usually not worth the money over the 2GB models and for high resolution gaming, it's often simply better to go for an AMD card 79xx card (or cards).

So if I could buy a 4gb 670 for roughly the same price of a 2gb 680 I should go for it? And no, I currently do not own either card.

If you find them for about the same price, then there's little reason to not go for the 4GB card. However, when I check, the prices are usually quite different, granted I haven't checked much in a while and could be out of date on GTX 670/680 4GB pricing.

The reason 4GB rarely makes a difference is that at 5760x1080 resolution, the frame buffers are still only ~25mb in size. So the difference between 1080p and 5760x1080 is less than 25mb of VRAM. However, AA has a tendency to eat vram as you push it up to higher numbers. So in order for the card to need more vram than 2GB, you'd have to push high levels of AA, but at that resolution, the performance hit is too high to use AA anyways.

It isn't until you push 3/4 way SLI that it becomes possible and maintain playable FPS.

4GB vs 2GB doesn't mean anything, both will perform fine because as you go up in resolution the vram usage only increases by 30mb or so, the only difference is displaying images(such as AA/AF/High graphical detail) on high resolution is much much more taxing than displaying it, on say, a lower resolution, like 1600x900 or 1920x1080.

However if those two are your only choices I'd go with a 2GB model because your games and applications will turn into a laggy mess far before 4GB is used, because of the 256-bit bandwidth. I'd just reccomend a 7970GHz edition, faster than a GTX680, and much better with higher resolutions.

4GB vs 2GB doesn't mean anything, both will perform fine because as you go up in resolution the vram usage only increases by 30mb or so, the only difference is displaying images(such as AA/AF/High graphical detail) on high resolution is much much more taxing than displaying it, on say, a lower resolution, like 1600x900 or 1920x1080.

However if those two are your only choices I'd go with a 2GB model because your games and applications will turn into a laggy mess far before 4GB is used, because of the 256-bit bandwidth. I'd just reccomend a 7970GHz edition, faster than a GTX680, and much better with higher resolutions.

Of the Radeon 6000 series, only the VLIW4 GPU-based cards from the Radeon HD 6000 series usually scaled very well. That would be only the Radeon 6930, 6950, 6970, and 6990. The rest were all VLIW5 cards of various generations (Radeon 6800 was an updated versions of it, Radeon 6700 and below was a direct copy of the Radeon 5000 implementation) and did not scale well and were much more stutter-prone in dual-GPU configurations.